Timing belt jumping / Belt Tensioner / Oil Pump

[JDWCruiserMS]

My timing jumped on my 02 LX for the second time in two years. This is my third timing belt in that same time period. The last time it jumped three teeth and the whole left bank quit firing. I believe it did the same thing this time. My mechanic replaced the belt, tensioner, and oil pump believing that the problem is coming from low oil pressure. Has anyone else has this issue?

 

[2001LC]

4.7L don't usually have issue with oil pressure. Even if they did, it would not cause a Timing belt to jump. At least not without cause so much damage elsewhere first, a Timing belt job alone, wouldn't get running.

Has it been same mechanic all three times.
Were cam seals ever done, at what mileage?

How many miles on it, between belt skips/all T-belt jobs?

 

[MJK]

If you had a new belt, tensioner and water pump and it skipped time - then it seems to me that something else is not right in there. Either install or?

Do the cams spin freely? Idler pulleys OK? Alignment? Engine is in time when assembled? Quality parts used? (Aisin or OEM)

If you had low oil pressure, then did that cause any problems in the (presumably left) head that increased friction? Worn cam bearing guides, scored cams, etc? This seems very unlikely, but perhaps worth yanking the valve cover to have a look.

 

[JDWCruiserMS]

4.7L don't usually have issue with oil pressure. Even if they did, it would not cause a Timing belt to jump. At least not without cause so much damage elsewhere first, a Timing belt job alone, wouldn't get running.

Has it been same mechanic all three times.
Were cam seals ever done, at what mileage?

How many miles on it, between belt skips/all T-belt jobs?

I bought the truck with 155k and it now has 175k. He said something to the extent of the tensioners for the timing belt were tied into the oil pump. Low oil pressure, low tension on the belt and hence the timing jump. No cam seals done under my watch. The belt has been replaced and reset three times since I’ve had it. Once at purchase, once last year, and now.

 

[JDWCruiserMS]

If you had a new belt, tensioner and water pump and it skipped time - then it seems to me that something else is not right in there. Either install or?

Do the cams spin freely? Idler pulleys OK? Alignment? Engine is in time when assembled? Quality parts used? (Aisin or OEM)

If you had low oil pressure, then did that cause any problems in the (presumably left) head that increased friction? Worn cam bearing guides, scored cams, etc? This seems very unlikely, but perhaps worth yanking the valve cover to have a look.
[/QUOTE

I’d agree but don’t know what else it could be. The truck runs like a top otherwise. No ticking, knocking, etc. it was running great when it jumped time this last time. It just started missing and my scan gauge through a random misfire code.

 

[94SRUNNER]

So what brand of parts were used and are you confident in your mechanic?

If you are in Madison, MS, then you are very close to a great Land Cruiser shop, 49 Tire Pros, in Richland, MS.

 

[AlpineAccess]

You need a new mechanic...

 

[Toyoland66]

I bought the truck with 155k and it now has 175k. He said something to the extent of the tensioners for the timing belt were tied into the oil pump. Low oil pressure, low tension on the belt and hence the timing jump. No cam seals done under my watch. The belt has been replaced and reset three times since I’ve had it. Once at purchase, once last year, and now.

The timing belt tensioner is a sealed assembly and exterior of the engine, it is not at all connected to the engine oiling system.

The fact that your mechanic said this after working on the engine and supposedly replacing it either makes him incompetent or a liar.

 

[ton504]

You need a new mechanic...

This. 100%. Do it before it cost you an engine.

The tensioner is a standalone piece. It does not work off of engine oil pressure. Get another timing belt and tensioner done else where. Water pump optional. Kind of hard to screw that up but I wouldn't put it past your “mechanic”.

 

[Toyoland66]

If I were you, considering the TB would normally be done at 180k and you have had issues 3 times in 20k, you should have the full timing belt job done with known good parts (Toyota or aisin) by a known good mechanic: timing belt, tensioner, idler, water pump

 

[MJK]

FYI: the tensioner is the thing in the upper left of this photo. The central pin is spring loaded and extends once you pull the 'grenade pin'. It presses on the lever end of the idler pulley bracket (lower left in this photo), pivoting the bearing in to provide constant belt tension independent of oil pressure. How or why anyone would say something different is completely beyond me, but the conclusion is the same.

God only knows what else other bumblefuckery has gone on with this guy. Cut your losses, take it to someone who knows what they are doing, ask them look it over and install Aisin or OEM belt and tensioner at minimum, and don't let him touch it again. Not even to put gas in it.

 

[2001LC]

I bought the truck with 155k and it now has 175k. He said something to the extent of the tensioners for the timing belt were tied into the oil pump. Low oil pressure, low tension on the belt and hence the timing jump. No cam seals done under my watch. The belt has been replaced and reset three times since I’ve had it. Once at purchase, once last year, and now.

As many have now posted, mechanic is wrong about tensioner. If he had changed it out, he would not think it's connected to engine oil system. So that's number one.

Where the tensioner may be shot, and allowed belt too slip. It's not likely, even if that's the factory tensioner. They do weaken and go bad. But not at 175K 99 out of 100 times.

Also mention earlier was the knock pin on cams. If this mechanic change the cam oil seals. He than may have set cam in wrong or not used a torque wrench. The likelihood he used a torque wrench on job is slim. As the FSM is needed for that, or at minmin the Aisin kit instruction. If he damage the knock pins, dealership will want to replace the camshafts. That will be very very pricy. I have worked around it. I do have a PN# for sub. Also your auto insurance may cover your cost. Sound rediculass I know, but call them. See what they say!

Timing belt job just done. Blown engine or savable? This is interesting guys!

Happy 2020 all. Well, I spent last day of 2019, inspecting a 2005 LC w/~200K, that was towed to me. That had a Timing Belt installed a few days before coming to me Let me know your thoughts: Blown engine from interference or is there hope? Also what do you think happened? Skip story and go...

forum.ih8mud.com

You need this done by a mechanic that has the factory service manual (FSM). Which gives step by step. Well kind of. Each year FSM has errors, but a mechanic can spot them and get done correct. Even than most miss a few details in the manul, resulting in oil leak.

You've given this guy 3 tries. Move on. Either find the local expect through mud or go to Toyota Dealership.

You're luck this is not the 06-07 VVT engine.


You can pull the tensioner and test it. FSM gives clear instruction on how.

 

[94SRUNNER]

As many have now posted, mechanic is wrong about tensioner. If he had changed it out, he would not think it's connected to engine oil system. So that's number one.

Where the tensioner may be shot, and allowed belt too slip. It's not likely, even if that's the factory tensioner. They do weaken and go bad. But not at 175K 99 out of 100 times.

Also mention earlier was the knock pin on cams. If this mechanic change the cam oil seals. He than may have set cam in wrong or not used a torque wrench. The likelihood he used a torque wrench on job is slim. As the FSM is needed for that, or at minmin the Aisin kit instruction. If he damage the knock pins, dealership will want to replace the camshafts. That will be very very pricy. I have worked around it. I do have a PN# for sub. Also your auto insurance may cover your cost. Sound rediculass I know, but call them. See what they say!

Timing belt job just done. Blown engine or savable? This is interesting guys!

Happy 2020 all. Well, I spent last day of 2019, inspecting a 2005 LC w/~200K, that was towed to me. That had a Timing Belt installed a few days before coming to me Let me know your thoughts: Blown engine from interference or is there hope? Also what do you think happened? Skip story and go...

forum.ih8mud.com

You need this done by a mechanic that has the factory service manual (FSM). Which gives step by step. Well kind of. Each year FSM has errors, but a mechanic can spot them and get done correct. Even than most miss a few details in the manul, resulting in oil leak.

You've given this guy 3 tries. Move on. Either find the local expect through mud or go to Toyota Dealership.

You're luck this is not the 06-07 VVT engine.


You can pull the tensioner and test it. FSM gives clear instruction on how.
View attachment 2375474
View attachment 2375476

Solid advice from one of the forums best!

 

[2001LC]

@JDWCruiserMS Can I ask why you had timing belt done at ~155K?

Was vehicle history pulled and no record of being done at ~90K or 7 years! Or did you buy with some mechanical condition, needing correcting!

 

[nissanh]

I did my T-Belt on my own for the first time! Just got the Mitsuboshi belt and AISIN T-belt kit and it is all good. Make sure you use good quality parts and a person who knows what he is doing.

 

[JDWCruiserMS]

@JDWCruiserMS Can I ask why you had timing belt done at ~155K?

Was vehicle history pulled and no record of being done at ~90K or 7 years! Or did you buy with some mechanical condition, needing correcting!

I requested it done when I purchased the truck.

 

[white_lx]

Did he forget to pull the pin on the tensioner? /s

Also no mention of water pump or ideler replacement. Maybe one of them is tight and dragging on the belt? And if he seriously replaced the oil pump, he went through a lot of trouble. That is not an easy job.

 

[ramangain]

Did your mechanic actually mean he suspects the oil damper inside of the tensioner? That would make more sense when looking at the FSM pic posted by @2001LC